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81.
沙丁胺醇在诱导培养人气管平滑肌细胞凋亡中的作用 总被引:10,自引:0,他引:10
目的 研究沙丁胺醇(商品名:舒喘灵)对于诱导培养人气管平滑肌细胞凋亡的作用。 方法 分离人气管平滑肌细胞并且在含有10%胎牛血清的达尔伯克改良伊格尔(DMEM)培养基中培养,4-6代的细胞用于实验。细胞用沙丁胺醇或色满卡林(cromakalim)或8-溴-环磷酸腺苷(Br-Camp)培养24h或48h ,光镜和电镜观察形态学改变。琼脂糖电泳分析DNA碎片。链亲和素-过氧化物酶(SP)免疫组化染色监测p53、Bcl-2和Bax基因表达的改变。通过破碎DNA的原位末端标记技术(TUNEL)检测凋亡细胞的百分数。结果 (1)沙丁胺醇或8-Br-cAMP降低存活细胞的数目。在48h、300μmol/L的浓度,存活的细胞数量最低;(2)人气管平滑肌细胞用沙丁胺醇(100μmol/L、300μmol/L)孵化48h显示出凋亡的形态学特征(细胞皱缩、染色质浓聚);(3)琼脂糖电泳显示,核酸DNA断裂片呈典型的梯状条带(大约180-200bp);(4)沙丁胺醇或8-Br-cAMP组p53或Bax基因表达显著高于对照组,但Bcl-2组基因表达低于对照组;(5)TUNEL显示,人气管平滑肌细胞的凋亡阳必用100、300μmol沙丁胺醇或100μmol8-Br-cAMP处理组与对照组比较差异有显著性(q分别为24.04、58.47、27.28,P均<0.001)。但cromakalim组和先用普萘洛尔(商品名:心得安)后与沙丁胺醇组与对照组比较,差异无显著性(q分别为0.12、0.53;P分别为0.932、0.717),不影响凋亡细胞的基本水平。结论 (1)在体外,沙丁胺醇以时间和浓度依赖的方式诱导人气管平滑肌细胞凋亡。(2)cAMP蛋白激酶A通路对于沙丁胺醇诱导的凋亡是必须的和充分的。 相似文献
82.
Schachter EN Zuskin E Goswami S Castranova V Arumugam U Whitmer M Siegel P Chiarelli A Fainberg J 《Lung》2005,183(1):63-71
Mushroom farm workers suffer from respiratory symptoms during the farming of mushrooms. The objective of this study was to analyze the effects of oyster mushroom (Pleurotus ostreatus) extract (OME) on isolated guinea pig tracheal smooth muscle in vitro. Isolated guinea pig tracheal tissue from 27 nonsensitized guinea pigs were studied. The OME was obtained from indoor mushroom growing fields and prepared as a 1:10 w/v aqueous solution. Dose-related contractions of nonsensitized guinea pig trachea were demonstrated using these extracts. The OME contained significant quantities of bacterial components (eg., endotoxin: 43,072.92 EU/mg). Parallel, pharmacological studies were performed by pre-treating the tissues with mediator-modifying agents including atropine, indomethacin, pyrilamine, BPB, acivicin, NDGA, captopril, TMB8 and capsaicin. Atropine consistently and strikingly reduced the contractile effects of this extract. These observations suggest an interaction of the OME with parasympathetic nerves or more directly with muscarinic receptors. Pretreatment with TMB8 (inhibitor of intracellular calcium mobilization) also significantly blocked the constrictor effect of OME, indicating a role of calcium mobilization in the constricting effect of OME. Inhibition of contraction by blocking of other mediators was less effective and varied depending on the drug. We conclude that OME causes a dose-related airway smooth muscle constriction by nonimmunological mechanisms involving a variety of airway mediators and possibly cholinergic receptors. This effect is not dependent on pre-sensitization of the guinea pigs. 相似文献
83.
Min-Soo Kim Jong Seok Lee Sang Beom Nam Hyo Jong Kang Ji Eun Kim 《Journal of Korean medical science》2015,30(8):1197-1202
Size selection of the laryngeal mask airway (LMA) Classic based on actual body weight remains a common practice. However, ideal body weight might allow for a better size selection in obese patients. The purpose of our study was to compare the utility of ideal body weight and actual body weight when choosing the appropriate size of the LMA Classic by a randomized clinical trial. One hundred patients with age 20 to 70 yr, body mass index ≥25 kg/m2, and the difference between LMA sizes based on actual weight and ideal weight were allocated to insert the LMA Classic using either actual body weight or ideal body weight in a weight-based formula for size selection. After insertion of the device, several variables including insertion parameters, sealing function, fiberoptic imaging, and complications were investigated. The insertion success rate at the first attempt was lower in the actual weight group (82%) than in the ideal weight group (96%), even it did not show significant difference. The ideal weight group had significantly shorter insertion time and easier placement. However, fiberoptic views were significantly better in the actual weight group. Intraoperative complications, sore throat in the recovery room, and dysphonia at postoperative 24 hr occurred significantly less often in the ideal weight group than in the actual weight group. It is suggested that the ideal body weight may be beneficial to the size selection of the LMA Classic in overweight patients (Clinical Trial Registry, ). NCT 01843270
Graphical Abstract
相似文献84.
目的探讨哮喘小鼠Th17细胞和CD4+CD25+调节性T细胞(Treg)在脾组织中表达水平的变化规律及与气道重塑的关系。方法将SPF级雌性Balb/c小鼠48只随机分为对照组和哮喘组,利用腹腔注射卵清蛋白(OVA)和氢氧化铝混悬液致敏及雾化吸入OVA激发制备哮喘气道重塑模型,对照组应用生理盐水替代。两组分别在雾化2周、4周及8周后的24 h内随机处死8只小鼠,左肺组织病理切片观察肺气道重塑程度;流式细胞仪测定脾组织中Th17、CD4+CD25+Treg细胞占CD4+T细胞的百分比。结果随着激发时间的延长,哮喘组支气管总管壁面积(Wat/Pbm)及支气管平滑肌面积(Wam/Pbm)逐渐增厚(P0.01);脾组织细胞悬液中Th17细胞水平逐渐升高,与气道重塑的程度呈正相关(P0.01),而CD4+CD25+Treg细胞水平逐渐降低,与气道重塑程度均呈负相关(P0.01)。结论哮喘小鼠气道重塑是动态变化的过程,激发的时间越长,气道重塑越严重,Th17细胞表达越高,CD4+CD25+Treg细胞表达越低,两者间免疫失衡可能是哮喘气道重塑发生的重要因素之一。 相似文献
85.
目的探讨气管插管在抢救急性重度有机磷中毒(ASOPP)患者的临床应用价值。方法回顾性分析2012年6月—2014年6月该院收治的52例行紧急气管插管后洗胃的急性重度有机磷中毒患者的临床资料,并与2010年5月—2012年5月收治的34例未实施气管插管的急性重度有机磷中毒患者临床资料进行对比观察。结果观察组52例患者中治愈47例,死亡2例,为多器官功能衰竭,自动放弃治疗3例,救治成功率为90.38%,明显高于对照组的58.82%;观察组入住重症监护室时间为(10.5±2.5)d,明显短于对照组的(15.7±3.9)d,差异具有统计学意义(P<0.05)。结论气管插管是救治急性重度有机磷中毒患者的有效措施,对于提高该类患者救治的成功率具有重要意义。 相似文献
86.
Erin R. Hanlin Jeffrey Zelenak Michael Barakat Kenton L. Anderson 《The American journal of emergency medicine》2018,36(9):1711-1714
Objective
Confirming correct endotracheal tube (ETT) placement is a key component of successful airway management. Ultrasound (US) as a tool for the confirmation of ETT placement has been investigated in the hospital setting but not in the pre-hospital setting. We hypothesized that after a short educational session, military flight medic trainees would be able to accurately identify ETT placement in a cadaver model.Methods
We conducted a prospective, randomized trial in a human cadaver model. Participants received a brief didactic and hands-on presentation on airway US techniques. Each participant then performed transtracheal US on cadaver models which were randomly assigned to tracheal or esophageal intubation; time to verbalize ETT location was also recorded. Participants were then asked whether they felt airway US would be a useful adjunctive skill in their practice.Results
Thirty-two military flight medic trainees were enrolled. US had a sensitivity of 66.7% and a specificity of 76.4% for identification of esophageal intubations. The positive predictive value was 71.4% and the negative predictive value was 72.2%. Mean time to report ETT placement was 47.3 s. Time did not vary between medics with accurate identification versus inaccurate identification (p = 0.176). 83% of participants felt airway US would be a useful adjunctive skill for the confirmation of ETT placement.Conclusions
Military flight medic trainees can rapidly use airway US to identify ETT placement after a short educational session with moderate sensitivity and specificity. These advanced military medics are interested in learning and implementing this skill into their practice. 相似文献87.
88.
《International journal of hygiene and environmental health》2015,218(4):386-391
BackgroundSeveral members of a swimming club complained of respiratory symptoms associated with attending a municipal indoor swimming pool. Trichloramine, a volatile chlorination by-product and a potent respiratory irritant, was the most probable culprit, but the exact cause for its presence in excessive concentrations remained elusive.MethodsTwenty-two competitive swimmers and six coaches were evaluated during the outbreak and nine swimmers and four coaches were re-evaluated one year later. Symptoms were recorded by non-standardized history taking; pulmonary function testing included spirometry, measurement of fraction of exhaled nitric oxide (FENO) and histamine provocation. Concentrations of trichloramine in air were measured repeatedly by the method of Héry.ResultsThe most commonly reported symptoms consisted of cough (n = 16), dyspnoea (n = 13), tearing eyes (n = 10) and blocked or runny nose (n = 6). Mean FEV1% predicted was 109.1%. Mean FENO level was 19.7 ppb (higher than 25 ppb in 3 subjects). Airway hyperreactivity to histamine (PC20 ≤ 8 mg/ml) was detected in 22/26 subjects. Measured trichloramine concentrations in air exceeded the maximal concentration (WHO) of 0.5 mg/m3 four times between May and October 2011 and four times between January and March 2012. Polyamine compounds, present in glue used for repairing pipework, were identified as a probable external source of nitrogen resulting in increasing trichloramine concentrations. After the removal of the presumed cause of the excessive trichloramine concentrations, most subjects improved clinically, but several subjects remained symptomatic and had bronchial hyperreactivity.DiscussionA high prevalence of airway hyperreactivity, accompanied by symptoms of upper and lower airways, was detected in swimmers who had been repeatedly exposed to high trichloramine concentrations. A glue containing polyamines, used to repair a pipework, was suspected to be the source of this excessive production of trichloramine. 相似文献
89.
目的 布地奈德(普米克令舒)联合沙丁胺醇雾化吸入治疗儿童哮喘急性发作前后气道炎性细胞、白介素6(IL-6)、IL-8、肿瘤坏死因子α(TNF-α)的变化,探讨其影响机制。方法 对急性哮喘发作患儿采用上述联合治疗1周,共对34例急性发作期、24例缓解期患儿和15例正常儿童的诱导痰液进行炎性细胞计数和分类,测定其中IL-6、IL-8、TNF-α水平。结果 急性组的总白细胞数,嗜酸粒细胞、中性粒细胞单核细胞比例及IL-6、IL-8、TNF-α水平均高于正常对照组。缓解组除嗜酸粒细胞及淋巴细胞比例明显高于正常对照组外,其余上述炎性细胞比例及细胞因子水平均降至正常。结论 普米克令舒联合沙丁胺醇雾化吸入可显著降低急性哮喘发作患儿气道分泌物内嗜酸粒细胞、中性粒细胞和单核细胞数量及IL-6、IL-8、TNF-α水平。 相似文献
90.